9,190 research outputs found
Анализ релейной защиты и автоматики района параллельных линий 110 кВ «Анжерская – Разъезд 3704» Кузбасской энергосистемы
Объектом анализа является релейная защита и автоматика района параллельных линий 110кВ «Анжерская – Разъезд 3704» Кузбасской энергосистемы Цель работы: анализ имеющегося оборудования защиты параллельных линий 110кВ, уставок защиты и согласованность степеней. В процессе исследования составлена схема замещения; рассмотрен состав защит линий и силовых трансформаторов; рассчитаны уставки и чувствительность защищаемой линии; обсуждены результаты выполненной работы.
В результате исследования была рассмотрена релейная защита и автоматика параллельной линии 110кВ «АнжерсThe object of analysis is the relay protection and automation area of parallel lines 110 "Anzherskaya - Departure of 3704" Kuzbass power system. Objective: To analyze the existing equipment protection of parallel lines of 110 kV, protection settings and consistency degrees
The study is made equivalent circuit; considered part of protection lines and power transformers; designed set point and the sensitivity of the protected line; We discussed the results of the work performed
Spectroscopy of the Clock Transition of Sr in an Optical Lattice
We report on the spectroscopy of the clock transition of atoms (natural linewidth of 1
mHz) trapped in a one-dimensional optical lattice. Recoilless transitions with
a linewidth of 0.7 kHz as well as the vibrational structure of the lattice
potential were observed. By investigating the wavelength dependence of the
carrier linewidth, we determined the magic wavelength, where the light shift in
the clock transition vanishes, to be nm.Comment: 4 pages, 4 figures, submitted to Phys. Rev. Lett. (09/May/2003
The Reaction 7Li(pi+,pi-)7B and its Implications for 7B
The reaction 7Li(pi+,pi-)7B has been measured at incident pion energies of
30-90 MeV. 7Li constitutes the lightest target nucleus, where the pionic charge
exchange may proceed as a binary reaction to a discrete final state. Like in
the Delta-resonance region the observed cross sections are much smaller than
expected from the systematics found for heavier nuclei. In analogy to the
neutron halo case of 11Li this cross section suppression is interpreted as
evidence for a proton halo in the particle-unstable nucleus 7B.Comment: 4 pages, 4 figure
Protein polymorphisms in strains of golden hamsters
At present only a few data is available about biochemical polymorphisms in the golden hamster. But the great number of strains of this species used in biomedical research requires the establishment of specific marker traits which can be used forgenetic control purposes.This study gives an overview on the degree of variability on the protein level among a series of 17 strains of hamsters.The results show 9 of about 40 stained isoproteins to express electrophoretic variants (22.5 %). Unexpectedly most of the phenotypes occur not only between but also within the strains despite more than 25 generations of inbreeding.The reason for this level of heterogeneity is not yet really obvious. Several possible points of influence are discussed, 0.3. an increased mutation rate or physiological specificities. At present, nongenetic reasons seem to be the most likely explanationfor most of the polymorphisms
Diffusion and jump-length distribution in liquid and amorphous CuZr
Using molecular dynamics simulation, we calculate the distribution of atomic
jum ps in CuZr in the liquid and glassy states. In both states
the distribution of jump lengths can be described by a temperature independent
exponential of the length and an effective activation energy plus a
contribution of elastic displacements at short distances. Upon cooling the
contribution of shorter jumps dominates. No indication of an enhanced
probability to jump over a nearest neighbor distance was found. We find a
smooth transition from flow in the liquid to jumps in the g lass. The
correlation factor of the diffusion constant decreases with decreasing
temperature, causing a drop of diffusion below the Arrhenius value, despite an
apparent Arrhenius law for the jump probability
Free triiodothyronine (T3) is negatively associated with fasting ghrelin serum levels in a population sample of euthyroid subjects
Purpose: Ghrelin is an orexigenic peptide hormone secreted in times of stress and hunger. It is deeply involved in the regulation of metabolism and energy homeostasis, promoting energy intake and inhibiting energy expenditure on a metabolic level. In this regard, it has in many ways antagonistic effect on the thyroid hormones, which increase metabolism and thus energy expenditure. While there is reasonable evidence of a negative association between ghrelin and hormones of the hypothalamic-pituitary-thyroid (HPT-) axis from studies in patients with thyroid dysfunction and small intervention studies, large-scale studies in healthy subjects are lacking. Therefore, we studied the relationship between total ghrelin serum levels and serum levels of the thyroid hormones in a large sample of euthyroid subjects. Methods: Total ghrelin, thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were determined after an overnight fast in 1666 subjects participating in a population-based cross-sectional study ('LIFE') including 10,000 adults. 1012 subjects were included in this analysis. Multiple linear regression analyses were performed. Results: FT3 was negatively associated with serum ghrelin; total sample: β = - 0.0001, p < 0.001; men: β = - 0.0002, p = 0.013; women: β = - 0.0001, p = 0.010, adjusted for age, BMI, alcohol consumption, serum levels of TSH and fT4 and smoking status. No associations were found between ghrelin serum levels and serum levels of fT4 or TSH. Conclusion: This is to date the largest study investigating the relationship between total serum ghrelin and thyroid hormones. The results point to a complex interaction and should initiate further research
- …